A research report submitted to the Faculty of Science, University of Witwatersrand, in partial fulfillment of the requirements for the degree of Master of Science of the School of Animal Plant and Environmental Sciences Johannesburg, 3rd November 2017. / Only one tetraploid (four sets of chromosomes) species of baobab (Adansonia digitata, L.) was recognized on mainland Africa. However, a study published in 2012 reported the existence of a new diploid baobab species known as Adansonia kilima which was said to co-exist on mainland Africa with A. digitata. This new species was identified on the basis of morphology (mainly floral and stomatal features), ploidy level and molecular phylogenetics. The two species of African baobabs were also differentiated according to their elevation preferences of between 650 m –1500 m above sea level (a.s.l.) and below 800 m a.s.l. for A. kilima and A. digitata respectively, which were said to rarely overlap. The report of this new species and the need to accurately determine the exact number of species of baobabs existing on mainland Africa have brought about a renewed interest in the study of the African baobabs and have necessitated this study. This research therefore compared A. digitata and A. kilima to assess the latter’s authenticity as described by work. The objectives were to (i) examine floral and stomatal traits from samples across mainland African baobab populations to establish whether there are distinct differences that can be correlated with altitudinal differences in order to distinguish the species present in Africa, and (ii) use stomatal size and density to infer ploidy levels of baobabs that occur at low and high altitudes. Herbarium and fresh specimens of A. digitata and A. kilima from across Africa with both leaves and flowers were borrowed from various herbaria to represent the widespread distribution of baobab in Africa. Cluster analysis (CA), Principal Component Analysis (PCA) and Non-metric Multi-dimensional Scaling (NMDS) of seven floral traits of 124 African baobab specimens were used to analyze baobabs that occur at low or high altitude. These specimens did not form distinct clusters or separate groupings correlated with either low or high altitude. The inference of ploidy using stomatal size categories as per previous study showed no differences in ploidy level among the baobabs studied and the difference in morphological features between baobabs found at low and high altitudes also could not be linked to inferred differences in ploidy levels. Specimens were assigned diploids or tetraploids based on their stomatal length as defined by an earlier work and the altitude of each specimen was used to ascertain whether the ploidy level correspond to the altitudinal category reported by a study published in 2012. Box and whisker plots were also used to compare the floral (pollen grain diameter, volume and density) and stomatal traits of baobabs that occurred at low and high altitudes. There was no statistical difference in the variation in floral features among African mainland baobabs found at low and high altitudes except in staminal tube length and style length. The stomatal traits results reveal that the mean stomatal length and density (per 1000 μm2) between baobabs that occur at low and high altitudes were not statistically different except when mean stomatal length and density were grouped into the two putative ploidy categories as per previous study. Morphological features results suggest that the differences in floral size, and stomatal size and density of mainland African baobabs could be related to differences in climate, water availability and geographical variation. Based on the data analyzed for this work, it is concluded that A. kilima is not distinct enough from A. digitata, to be recognized as a new species. However, further research should investigate potential variation in genome size among African baobab that is correlated with altitude using flow cytometry analysis and/or chromosome counts. Key words: altitudinal variation, mainland African baobab, multivariate analysis, ploidy level, pollen grains, species concept, stomatal density, sympatric speciation. / LG2018

Abstract Recently there has been a renewed impetus in the search for novel ingredients to be used in the cosmeticindustry and Baobab (Adansonia digitata L., Malvaceae) seed oil has received high interest. In this study,a commercial Baobab seed oil sample was characterised (fatty acid content) using GCxGC-ToF-MS and apilot study on the safety and efficacy of the seed oil was performed. The safety and efficacy of Baobab seedoil after topical application was determined using healthy adult female caucasian participants (n = 20).A 2× magnifying lamp was used for visual analysis, while for monitoring and evaluation of the irritancylevel, transepidermal water loss (TEWL) and hydration level of the skin, Chromameter®, Aquaflux®andCorneometer®instruments, respectively, were used. In addition, Aquaflux®and Corneometer®instru-ments were used to assess occlusive effects. Thirteen methyl esters were identified using GCxGC-ToF-MS.The major fatty acids included 36.0% linoleic acid, 25.1% oleic acid and 28.8% palmitic acid with 10.1%constituting trace fatty acids. The irritancy of sodium lauryl sulphate (SLS) in the patch test differedsignificantly compared to both de-ionised water (p < 0.001) and Baobab seed oil (p < 0.001) but the dif-ference between the irritancy of Baobab seed oil and de-ionised water was not significant (p = 0.850).The moisture efficacy test indicated a reduced TEWL (p = 0.048) and an improved capacitance moistureretention (p < 0.001) for all the test products (Baobab oil, liquid paraffin, Vaseline®intensive care lotionand Vaseline®). The occlusivity wipe-off test indicated an increased moisture hydration (p < 0.001) anddecreased TEWL particularly when Baobab oil was applied. Baobab possesses hydrating, moisturising andocclusive properties when topically applied to the skin. Baobab seed oil could be a valuable functionalingredient for cosmeceutical applications.

Caption: “Water-home sewerage in a Baobab Tree at Mutino-Mulilo (?Katima), Eastern Caprivi. Headquarters of Major Trollip, Native Commissioner. Ca. 1940’s”

@Adansonia digitata@L. (Malvaceae) is a huge multipurpose tree of the savannahs of sub-Saharan Africa with high economic potential for local communities. The edible fruits and leaves are known for their high nutritional values and can be used fresh or processed. However, a high intra-specific variability regarding morphology, genetics and nutritional content of baobab and its products is documented for several African regions, while data for Kenya is largely lacking. This study aimed at documenting the genetic and morphological variability of baobab accessions in Kenya and at checking the presence of the newly described diploid baobab species @Adansonia kilima@. Samples were collected from 204 baobab trees from seven populations defined by geographical distance in South-eastern and Coastal Kenya at altitudes of 6-1,058 m asl. Leaf or bark samples for genetic diversity assessment were collected from all 204 trees, while leaves only from 65 and fruits from 76 trees (all in inland locations) for morphological analyses based on the publication Descriptors for Baobab. Nine microsatellite loci were used to assess genetic variation and results analysed with specific software because of the tetraploid nature of baobab. Overall genetic diversity was high and all loci were polymorphic. The mean gene diversity was 0.803 and observed heterozygosity was 0.907. Analysis of molecular variance (AMOVA) revealed low variation among populations (12.4%) and high variation within populations (87.6%). Bayesian clustering and Principal Coordinate Analysis divided the accessions into two clusters, one with only inland and one with coastal accessions. Although the presence of @Adansonia kilima@ was previously postulated for Kenya, flow cytometry did not detect any among the analysed samples as only tetraploids were observed. Regarding morphological characteristics, no differences among the fruit accession from inland populations were found (no fruits were collected in coastal areas). Leaf morphological data showed significant differences between inland and coastal populations with longest leaflets and leaf petioles in accession from the Coast, thus confirming the results obtained for genetic analysis. This study contributes to the overall knowledge of the genetic diversity of baobab in Kenya and can contribute to the development of germplasm conservation strategies and domestication programs for baobab.

Thesis (M. A. (Anthropology)) --University of Limpopo, 2016. / The baobab tree (Adansonia digitata), with more than 300 cultural and ethnobotanical uses in Africa has been identified as one of the most important savanna trees to be conserved, domesticated and valorised on the continent. A decline in baobab populations due to overexploitation could have a significant negative effect on African livelihoods. Therefore, it is important to determine potential strategies for the conservation of this tree species. The study aimed to explore the cultural significance and ethnobotanical use, as well as conservation of baobab trees by the Sagole community in the Vhembe District of the Limpopo Province, South Africa. Furthermore, the conservation efforts of this community and the provincial government were also elucidated. In the Sagole community 40 local community members, aged 20 years and older, were selected via convenience sampling. A semi-structured questionnaire was employed to collect information on the cultural significance of baobab trees to members of this community. Research questions focussed specifically on identifying folk taxonomy, the transfer of species-specific information to younger generations, and cultural taboos pertaining to the baobab. It has been discovered that young people of Sagole are not well versed in the cultural value pertaining to baobabs. Furthermore, members of the community and the village head (chief) have limited knowledge related to taboos associated with this species. Thus, when individuals transgressed a taboo related to this tree species there is no formal punishment. Sagole community members use baobab trees for various purposes such as food and medicine. The species is used medically to cure various ailments. Most inhabitants in the community harvest this tree. The most common plant parts harvested for cultural use are the fruits, bark, roots and leaves. However, community members have limited knowledge about the taboos related to harvesting of this majestic tree.

Le baobab est un arbre qui pousse à l'état sauvage en Afrique et ailleurs dans le monde où le fruit est consommé sous différentes formes. Si l'écologie et la botanique de la plante ont été bien étudiées, il y a peu d'information disponible sur la composition biochimique d'une manière générale et même inexistante chez les espèces malgaches en particulier. Cette étude s'inscrit dans le contexte du développement et de la valorisation des produits locaux en Afrique. Elle a pour objectif principal de mieux caractériser la pulpe des fruits de baobabs issus d'échantillons de diverses provenances de Madagascar et d'Afrique. A cette fin, elle s'est attachée dans un premier temps à caractériser et à quantifier les principaux éléments nutritifs comme les glucides, les acides aminés, les lipides, les polyphénols, la vitamine C, les acides organiques, les éléments minéraux et les arômes. La caractérisation biochimique de la pulpe a révélé une forte acidité titrable (102 meq/100g) et une teneur élevée en acide ascorbique (jusqu'à 312 mg/100g) et en polyphénols de (60,24 à 137,81mg/100g et de 329 à 1705,98 mg/100g) ainsi qu'un potentiel antioxydant très fort et une bonne source de Ca 658 mg/100g.Une évaluation du potentiel de ce fruit pour une valorisation à plus grande échelle à travers une amélioration des procédés de transformation existant en Afrique a été réalisée. L'identification d'une approche de stabilisation et de conservation du nectar par voie conventionnelle (pasteurisation) a été réalisée. Nos résultats ont montré que le nectar est aussi nutritif que les fruits usuels et que sa stabilisation peut se faire par une pasteurisation en utilisant le barème 70°C/10 min. L'analyse sensorielle du nectar après chaque étape de traitement ou de conservation (42 j) n'a pas montré de modification organoleptique du produit quelque soit la température de stockage Deux approches empiriques classiques (modèles d'Arrhenius et de Ball) ont été utilisés pour décrire la cinétique de dégradation thermique de la vitamine C du nectar.Enfin, une étude de faisabilité de l'utilisation de la spectrométrie proche infrarouge pour la caractérisation des origines et pour la détermination des teneurs en constituants biochimiques a été réalisée. Ce travail a permis de montrer qu'il était possible de doser la matière sèche, les protéines, le fructose et le potassium.Une séparation des espèces basée sur l'analyse des spectres semble aussi pouvoir être réalisée via leur appartenance aux sections (brevetubae, longitubae). / Baobab tree is growing wild in Africa and elsewhere in the world. Fruits are consuming in different ways. Plant ecology and botanic are well detailed, but generally few information is available on biochemical composition and even nothing about Malachi species. This study takes place in the development and valorization of African local fruits program. The main objective is to characterize baobab fruit pulp samples coming from both Madagascar and Africa. First, the main nutriments were characterized and quantified, such as, carbohydrates, amino acids, lipids, polyphenols, vitamin C, organic acids, minerals and aroma compounds. Biochemical characterization of the pulp showed high level of total acidity (102 meq/100g), ascorbic acid (till 312 mg/100g), polyphenols (from 60.24 to 137.81mg/100g) and anti oxidant potential.To valorize the fruit at larger scale, evaluation of its potential was realized trough improvements of existing processing techniques in Africa. A conventional approach (pasteurization) was realized to stabilize and store nectar. Data show nectar is as nutritive than fresh fruit with pasteurization schedule at 70°C/10min. Sensory analysis of nectar after each step of process doesn't show organoleptic difference relative to storage temperature. Two classical empirical approaches (Arrhenius and Ball models) were used to describe kinetic of thermal degradation of C vitamin of nectar.At least, Near Infra Red Spectroscopy (NIRS) was tested, to determine geographical origins and levels of biochemical compounds. Dry matter, proteins, fructose and potassium were quantified. Species segregation with NIRS seems possible by means of belonging to brevetubae and longitubae sections.

Tree species belonging to the genus Acacia have a significant impact ecologically and economically in southern Africa. Together with the African baobab, these trees are recognized as icons of the African landscape. They are widely distributed in this area and extensively used by local communities as sources of energy, stock feed, medical remedies and building material. There is still a substantial lack of knowledge regarding the ecological association between these plants and other living organisms such as fungi. This is, however, not new to the African continent where fungi are generally poorly studied and collected, and it is envisaged that many new fungal species will be discovered as scientists focus their efforts more on this geographical niche. An example of the lack of knowledge on the fungal biodiversity in Africa is reflected in the limited reports of members of the Botryosphaeriaceae, described to date from Acacia spp.. A review on phytopathogens in South Africa by Crous et al. (2000) indicated no records of the Botryosphaeriaceae associated with native Acacia spp. Despite the importance of many species within the Botryosphaeriaceae as pathogens, knowledge about the true diversity and taxonomy of species in this family is limited, especially where native plant communities are concerned. This dissertation attempts to contribute to knowledge on the associations between members of the Botryosphaeriaceae and indigenous Acacia trees in southern Africa, and the possible role they may play in diseases of these trees. Chapter 1 represents a literature review that focuses on fungi previously associated with Acacia spp. on the African continent. Information provided in this chapter refers to available reports on pathogens and saprophytes occurring on Acacia spp. that are both native and nonnative to Africa. Special reference is made to those occurring in southern Africa. Due to the concern of the introduction of new pathogens in areas where native and non-native plants are co-existing, emphises is also placed on the possibility of pathogen-host jumps between native and non-native Acacia spp. The potential threat they might pose to the future biosecurity of these important trees is discussed. Acacia mellifera, also known as the blackthorn, is one of the native African Acacia spp. that has been extensively studied. This tree is threatened by a serious die-back disease with symptoms similar to the die-back typically caused by members of the Botryosphaeriaceae. In an effort to understand the association of the Botryosphaeriaceae with native Acacia spp. in southern Africa, a study was undertaken to search for the presence of these fungi on especially A. mellifera in Namibia and the Pretoria area in South Africa. Other Acacia spp. were also sampled in cases where they were present in the same areas as A. mellifera. These results are presented in chapter 2. In a previous study, the fungal diversity of native trees and plant species in the Northern Cape Province of South Africa was studied. This resulted in the isolation of a number of fungi that resembled the morphological characteristics of the Botryosphaeriaceae. In chapter 3, these fungi were further identified to species level based on morphological and phylogenetic characteristics. In chapter 4 an attempt was made to compare the Botryosphaeriaceae that are associated with important native trees with those occurring on non-native trees. To accomplish this, a pilot study was done to investigate the presence of the Botryosphaeriaceae on A. mearnsii in the Gauteng Province of South Africa. Results from chapters 2 and 3 on native Acacia spp. from Namibia and South Africa served as the bases of comparison for this chapter. Results of previous studies that investigated diseases of plantation grown A. mearnsii were also included for comparison. Lastly, a summary is included to review the results of this study and also the significance and impact these results made, not only on the taxonomy of the Botryosphaeriaceae, but also understanding the fungal biodiversity of indigenous tree species in southern Africa. To date, this is the most extensive study of the Botryosphaeriaceae associated with native African Acacia spp. and it is also the first study that resulted in the describtion of so many new species in this group of fungi from a single host. Results from this study indicated that there is a significantly greater diversity in the Botryosphaeriaceae associated with native Acacia spp. in southern Africa than was previously thought. This dissertation attempts to form the basis for future studies to finally understand the interactions between the Botryosphaeriaceae and their native hosts as well as their role and threat as pathogens to indigenous and economically important plants. Copyright / Dissertation (MSc)--University of Pretoria, 2009. / Microbiology and Plant Pathology / unrestricted

Les lipases présentent un grand intérêt pour la synthèse du Biodiesel, carburant alternatif au gasoil, généralement obtenu d’une transestérification des triacylglycérols avec un alcool, la plupart du temps le méthanol. Pour avoir un ester issu totalement de la biomasse végétale, l’éthanol peut être utilisé comme accepteur d’acyle. L’objectif de cette étude est de développer des procédés enzymatiques de synthèses d’esters éthyliques catalysés par les lipases végétales sous leur forme brute avec des intrants (huile et alcool) d’origine végétale. D’abord, elle a consisté à la mise en évidence d’une activité lipasique pour des réactions d’éthanolyse et d’hydrolyse par les graines d’A. suarezensis, d’A. grandidieri, de J. curcas, de J. mahafalensis, de M. oleifera et de M. drouhardii. Ensuite, les influences de certains facteurs sur la capacité des extraits le(s) plus actif(s) à réaliser des réactions d’éthanolyse en milieux non aqueux, aqueux et en utilisant comme substrat leurs lipides natifs ont été étudiées. Enfin, des essais de combustion ont été menés sur un moteur monocylindre à injection directe pour l’étude des performances, des émissions et de la combustion du biodiesel produit et de ses mélanges avec le gasoil. Toutes les graines germées sont dotées d’une activité en hydrolyse et éthanolyse. La poudre d’A. grandidieri est la plus active en éthanolyse. Avec cette dernière, deux procédés ont pu être développés : un en milieu non aqueux et un en milieu aqueux (respectivement un rendement de 96,2 % et 96,3 %). Elle est aussi capable de transformer ses lipides natifs sans extraction au préalable en esters éthyliques (rendement de 91,6%). Les performances et la combustion du biodiesel et de ses mélanges sont similaires à celle du gasoil. Une réduction significative des émissions de CO, NOX, CO2 et SO2 au cours de la combustion du biodiesel et de ses mélanges est observée. Ces résultats montrent que les lipases végétales exploitées sous leurs formes brutes peuvent être une alternative aux lipases microbiennes et aux catalyseurs chimiques. / There is a great interest in the use of lipase in the production of Biodiesel, alternative diesel fuel, usually obtained from a transesterification of triacylglycerol with an alcohol which is mostly methanol. To have a biodiesel derived totally from vegetable biomass, ethanol must be explored as acyl acceptor. The objective of this work is to develop enzymatic processes for the synthesis of ethyl esters catalyzed by plant lipases in their crude form with all inputs (oil and alcohol) of origin plant. Firstly, the hydrolysis and ethanolysis activities of A. suarezensis, A. grandidieri, J. curcas, J. mahafalensis, M. oleifera and M. drouhardii seeds were assessed. Subsequently, the most active(s) plant lipase(s) was selected to study the effects of some factors on their ability to carry out ethanolysis reactions in nonaqueous, aqueous media and using as substrate their lipids. Finally, combustion tests were carried out on a single cylinder direct injection engine to study the performance, emissions and combustion of biodiesel and its mixture with diesel. All germinated seeds have hydrolysis and ethanolysis activity. The most active in ethanolysis is the powder from A. grandidieri seed. With this powder, two processes were developed: one in nonaquous medium and the other in aqueous medium (yield of 96.2 % and 96.3 %, respectively). Lipase from A. grandidieri seed is able to transesterify its oils without an extraction thereof into ethyl ester. Performance and combustion characteristics of biodiesel and its mixtures are similar to that of diesel fuel. A significant reduction in CO, NOX, CO2 and SO2 emissions during the combustion of biodiesel and its mixtures is observed. These results show that plant lipases exploited in their crude form can be an alternative to microbial lipases and chemical catalysts.

Der Baobab (Adansonia digitata) ist ein mächtiger und laubabwerfender Baum, der im Sudan heimisch ist. Neben den Früchten bietet er eine Vielzahl von Verwendungsmöglichkeiten u.a. als Nahrungs- und Heilmittel. Die Tamarinde (Tamarindus indica) ist ein graziöser und immergrüner Baum, der im Sudan verbreitet ist. Die Früchte sind bei der Bevölkerung sehr begehrt. Weiterhin ist er Grundlage für viele Forstprodukte. Im Zentralsudan konnten weitere Wildobstarten identifiziert werden, die zur Sicherung der Nahrungsgrundlage der ländlichen Bevölkerung in den Savannen beitragen. Vor allem im Nordsudan existieren große, potenzielle Agrarflächen, auf denen die Bodenversalzung als limitierender Faktor wirkt. Um Nahrungssicherheit für die zunehmende Bevölkerung zu gewährleisten, erlagen diese marginalen Flächen immer mehr an Bedeutung. Die Gewächshausversuche über einen Zeitraum von 20 Wochen zeigten, dass bei Adansonia digitata-Sämlingen das Wachstum und der Stoffwechsel bereits bei Salzbelastungen von 20 mM NaCl stark beeinflusst wurden. Daher kann diese Art im Sämlingsstadium als sehr salzempfindlich eingestuft werden. Tamarindus indica-Sämlinge tolerierten Salzbelastungen von 40 mM NaCl. Daraus folgt, dass die Tamarinde im Vergleich zu anderen Obstarten im Sämlingsstadium relativ salzverträglich ist. Unter den gegebenen Versuchsumständen ist zu vermuten, dass die Tamarinde eher geeignet scheint für die Kultivierung in salzbelasteten semiariden Gebieten. / The Baobab (Adansonia digitata) is a massive, deciduous tree and native to Sudan. Beside its fruits, the Baobab has an exceedingly wide range of uses ranging from food and beverages to medicinal uses. The tamarind (Tamarindus indica) is an aesthetic, evergreen tree and grows wild throughout Sudan. Its fruits are highly appreciated by the people. In addition, the tree provides a diversity of further important forest products. A number of under-utilised species with edible fruits were identified in Central Sudan. Fruits of these indigenous species play an important role in the diet of rural people in the savanna belt, especially during famines and food shortages. Particularly in Northern Sudan there are vast areas of potentially arable land which are affected by salinity to variable degrees. In order to maintain food security for the increasing population, this land is becoming more and more important. The results of the greenhouse experiments over a period of 20 weeks indicate that a salinity level of 20 mM NaCl strongly influences growth and metabolism of Adansonia digitata seedlings. Therefore in the seedling stage the species can be characterised as salt-sensitive. Tamarindus indica seedlings tolerated a salinity level of 40 mM NaCl. This indicates that in the seedling stage tamarind is a fairly salt tolerant tree species compared to other fruit trees. The conclusion of the greenhouse experiments indicates that the tamarind seems to be the more suitable under-utilized fruit tree species for cultivation in semi-arid areas with salinity problems.

Thesis (M. A. (Anthropology)) -- University of Limpopo, 2016 / The baobab tree (Adansonia digitata), with more than 300 cultural and ethnobotanical uses in Africa has been identified as one of the most important savanna trees to be conserved, domesticated and valorised on the continent. A decline in baobab populations due to overexploitation could have a significant negative effect on African livelihoods. Therefore, it is important to determine potential strategies for the conservation of this tree species. The study aimed to explore the cultural significance and ethnobotanical use, as well as conservation of baobab trees by the Sagole community in the Vhembe District of the Limpopo Province, South Africa. Furthermore, the conservation efforts of this community and the provincial government were also elucidated. In the Sagole community 40 local community members, aged 20 years and older, were selected via convenience sampling. A semi-structured questionnaire was employed to collect information on the cultural significance of baobab trees to members of this community. Research questions focussed specifically on identifying folk taxonomy, the transfer of species-specific information to younger generations, and cultural taboos pertaining to the baobab. It has been discovered that young people of Sagole are not well versed in the cultural value pertaining to baobabs. Furthermore, members of the community and the village head (chief) have limited knowledge related to taboos associated with this species. Thus, when individuals transgressed a taboo related to this tree species there is no formal punishment. Sagole community members use baobab trees for various purposes such as food and medicine. The species is used medically to cure various ailments. Most inhabitants in the community harvest this tree. The most common plant parts harvested for cultural use are the fruits, bark, roots and leaves. However, community members have limited knowledge about the taboos related to harvesting of this majestic tree.